Skeletal System

Skeletal system/tissues

Joints

Skeletal muscle

Major function

Major structural components

Compact bone & spongy bone char.

Components of long bone

Red & yellow bone marrow

Types of bone cells

Support, assistance in movement, protection, mineral storage, blood cell formation, energy storage

35% organic bone tissue (bone, connective tissue, cells, ex. matrix, collagen), 65% inorganic - minerals, fibrocartilage, hyaline cartilage, articular cartilage

Compact - on every bone, perforating canal, periosteum (dense irregular) Spongy - osteocytes, ex. martix, no osteons, in sections of long and flat bone, endosteum (layer)

Epiphysis w/ epiphyseal line, articular cartilage, compact bone (w/ periosteum), diaphysis (shaft), medullary cavity (marrow, lined w/ endosteum), periosteum

Composition

Red bone marrow - gelatinous, soft tissue. Yellow bone marrow - adipose tissue

Function

Red bone marrow - blood cell formation. Yellow bone amrrow - nutrient storage

Osteogenic (stem) cells - (periosteum and endosteum), osteoblast - (create ex. matrix), osteoclasts - (endosteum)

Fibrous joints

Cartilaginous joints

Synovial joints

6 types of synovial joints

Where two bones meet, short interconnecting fibers. Suture - skull only, no movement. Syndesmosis - D.R.C.T, little movement, distal tibiofibular. Gumphosis - tooth meets alveolus, immovable, periodontal ligaments

Synchondrosis - hyaline cartilage, between 1st ri and manubrium, epiphyseal plates. Symphysis - pubic symphysis and intervertebral joints (fibrocartilage, hyaline cartilage). Slightly movable.

Movable joints. Joint capsule with inner (areolar CT) & outer layer (D.I.C.T). Joint cavity filled w/ synovial fluid (lubricating, shock absorber, nourishes articular cartilage).

Plane joint

Hinge joint

Pivot joint

Condylar joint

Saddle joint

Ball-and-socket joint

Gliding movement, intercarpal and intertarsal joints, joints b/w vertebral articular surfaces

Flexion and extension, elbow joints and b/w phalanges

Rotation, radius and ulna, atlas C1 and C2 joint

Flexion and extension, adduction and abduction, metacarpophalangeal (knuckle) and wrist joints

Flexion and extension, adduction and abduction, only in thumbs

Flexion and extension, adduction and abduction, rotation, shoulder and hip joints

Functions

Properties

Connective tissue layers

Components of skeletal fiber

Contractility - myofilaments, shortening of muscle cells. Excitability - nerve signals which stimulate muscle cells. Extensibility - stretching. Elasticity - stretch and recoil.

Produce movement, open/close body passageways, maintain posture and stabilize joints, generate heat

Epimysium - surrounds the outer layer of skeletal muscle (D.R.C.T). Perimysium - "around the muscle", fasicles. Endomysium - Within a fascicle.

Myofibrils - Unbranched cylinders, contain myofilaments which contract protein. Mitochondria - Supply energy for muscle contraction. Sarcoplasmic reticulum - Smooth ER which surround each myofibril. T tubules - Deep invaginations of the sarcolemma that run b/w terminal cisterns.